P3862 Counting Cycles
Description
Compute the number of cycles in the undirected complete graph on $n$ vertices after deleting one edge, and output the answer modulo $998244353$.
Note: A “cycle” means choosing any vertex as the starting point, following non-repeating edges, visiting non-repeating vertices along the way, and then returning to the starting vertex to form a closed path.
Input Format
The first line contains an integer $T$, indicating the number of test cases.
The next $T$ lines each contain an integer $n$, as described above.
Output Format
Output $T$ lines, each containing one integer, representing the answer.
Explanation/Hint
For the first $10\%$ of the testdata, $3 \leq n \leq 10$.
For an additional $20\%$ of the testdata, $ 9.99\times 10^2 \leq n \leq 10^3$.
For an additional $30\%$ of the testdata, $ 9.99\times 10^4 \leq n \leq 10^5$.
For the remaining $40\%$ of the testdata, $ 9.99\times 10^8 \leq n \leq 10^9$.
All testdata satisfy $1 \leq T \leq 10$.
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